Numerous therapeutic and diagnostic monoclonal antibodies (MAbs) are used in the clinical setting to treat and diagnose human diseases, for example, cancer and autoimmune diseases. For example, exemplary therapeutic antibodies include Rituxan (Rituximab), Herceptin (Trastuzumab), Avastin (Bevacizumab) and Remicade (Infliximab). In designing antibody therapeutics, it is desirable to create antibodies, for example, antibodies that modulate a functional activity of a target, and/or improved antibodies such as antibodies with higher specificity and/or affinity and/or and antibodies that are more bioavailable, or stable or soluble in particular cellular or tissue environments. It is among the objects herein to provide methods for optimizing and improving the binding affiniites of antibodies and for selecting antibodies with desired affinities.